Genes and mechanisms in Arabidopsis innate immunity against Leptosphaeria maculans

摘要: Leptosphaeria maculans is a hemibiotrophic ascomycete that causes blackleg disease on Brassica oilcrops, which globally great threat for oilseed production. In order to obtain mechanistic understanding of this devastating pathogen, Arabidopsis thaliana was used as model host. Susceptible genotypes facilitated identification the mechanisms required resistance. The phytoalexin camalexin first identified quantitative resistance factor; whereas accelerated cell death mutants enabled pathogen circumvent by switching necrotrophic mode growth. addition this, eleven susceptible (lms) were identified, one accession (An-1) and 1:15 loss in F2 progenies from resistant accessions Ler-0 Col-0. transgressive segregation revealed dependent TIR-NB-LRR genes (RLM1Col RLM2Ler), independent signalling components previously associated all genes. RLM1Col found be responsible L. induced callose depositions. A segregant analysis transcriptomes Col-0 x An-1 F3 lines region chromosome 4 with significantly more highly expressed progenies. T-DNA insertion over expression studies N-terminal part TIR-NB gene maculans, Alternaria brassicae, A. brassicicola Botrytis cinerea. contrast other pathogens, phytohormones salicylic acid (SA), jasmonic (JA) ethylene (ET). establish physiological resistances, characterized defective hormone responses screened. Mutants ABA biosynthesis impair both manner. Further defence pathways influences combinations SA, JA ET growth when R resistances disrupted. Taken together, work describes establishment new pathosystem well-characterized host organisms, display novel features overlapping biotrophic pathosystems.